1 /*
2 * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.nio.cs;
27
28 import java.nio.ByteBuffer;
29 import java.nio.CharBuffer;
30 import java.nio.charset.Charset;
31 import java.nio.charset.CharsetDecoder;
32 import java.nio.charset.CharsetEncoder;
33 import java.nio.charset.CoderResult;
34
35 public class US_ASCII
36 extends Charset
37 implements HistoricallyNamedCharset
38 {
39 public static final US_ASCII INSTANCE = new US_ASCII();
40
41 public US_ASCII() {
42 super("US-ASCII", StandardCharsets.aliases_US_ASCII());
43 }
44
45 public String historicalName() {
46 return "ASCII";
47 }
48
49 public boolean contains(Charset cs) {
50 return (cs instanceof US_ASCII);
51 }
52
53 public CharsetDecoder newDecoder() {
54 return new Decoder(this);
55 }
56
57 public CharsetEncoder newEncoder() {
58 return new Encoder(this);
59 }
60
61 private static class Decoder extends CharsetDecoder {
62
63 private Decoder(Charset cs) {
64 super(cs, 1.0f, 1.0f);
65 }
66
67 private CoderResult decodeArrayLoop(ByteBuffer src,
68 CharBuffer dst)
69 {
70 byte[] sa = src.array();
71 int sp = src.arrayOffset() + src.position();
72 int sl = src.arrayOffset() + src.limit();
73 assert (sp <= sl);
74 sp = (sp <= sl ? sp : sl);
75 char[] da = dst.array();
76 int dp = dst.arrayOffset() + dst.position();
77 int dl = dst.arrayOffset() + dst.limit();
78 assert (dp <= dl);
79 dp = (dp <= dl ? dp : dl);
80
81 try {
82 while (sp < sl) {
83 byte b = sa[sp];
84 if (b >= 0) {
85 if (dp >= dl)
86 return CoderResult.OVERFLOW;
87 da[dp++] = (char)b;
88 sp++;
89 continue;
90 }
91 return CoderResult.malformedForLength(1);
92 }
93 return CoderResult.UNDERFLOW;
94 } finally {
95 src.position(sp - src.arrayOffset());
96 dst.position(dp - dst.arrayOffset());
97 }
98 }
99
100 private CoderResult decodeBufferLoop(ByteBuffer src,
101 CharBuffer dst)
102 {
103 int mark = src.position();
104 try {
105 while (src.hasRemaining()) {
106 byte b = src.get();
107 if (b >= 0) {
108 if (!dst.hasRemaining())
109 return CoderResult.OVERFLOW;
110 dst.put((char)b);
111 mark++;
112 continue;
113 }
114 return CoderResult.malformedForLength(1);
115 }
116 return CoderResult.UNDERFLOW;
117 } finally {
118 src.position(mark);
119 }
120 }
121
122 protected CoderResult decodeLoop(ByteBuffer src,
123 CharBuffer dst)
124 {
125 if (src.hasArray() && dst.hasArray())
126 return decodeArrayLoop(src, dst);
127 else
128 return decodeBufferLoop(src, dst);
129 }
130 }
131
132 private static class Encoder extends CharsetEncoder {
133
134 private Encoder(Charset cs) {
135 super(cs, 1.0f, 1.0f);
136 }
137
138 public boolean canEncode(char c) {
139 return c < 0x80;
140 }
141
142 public boolean isLegalReplacement(byte[] repl) {
143 return (repl.length == 1 && repl[0] >= 0) ||
144 super.isLegalReplacement(repl);
145 }
146
147 private final Surrogate.Parser sgp = new Surrogate.Parser();
148 private CoderResult encodeArrayLoop(CharBuffer src,
149 ByteBuffer dst)
150 {
151 char[] sa = src.array();
152 int sp = src.arrayOffset() + src.position();
153 int sl = src.arrayOffset() + src.limit();
154 assert (sp <= sl);
155 sp = (sp <= sl ? sp : sl);
156 byte[] da = dst.array();
157 int dp = dst.arrayOffset() + dst.position();
158 int dl = dst.arrayOffset() + dst.limit();
159 assert (dp <= dl);
160 dp = (dp <= dl ? dp : dl);
161
162 try {
163 while (sp < sl) {
164 char c = sa[sp];
165 if (c < 0x80) {
166 if (dp >= dl)
167 return CoderResult.OVERFLOW;
168 da[dp] = (byte)c;
169 sp++; dp++;
170 continue;
171 }
172 if (sgp.parse(c, sa, sp, sl) < 0)
173 return sgp.error();
174 return sgp.unmappableResult();
175 }
176 return CoderResult.UNDERFLOW;
177 } finally {
178 src.position(sp - src.arrayOffset());
179 dst.position(dp - dst.arrayOffset());
180 }
181 }
182
183 private CoderResult encodeBufferLoop(CharBuffer src,
184 ByteBuffer dst)
185 {
186 int mark = src.position();
187 try {
188 while (src.hasRemaining()) {
189 char c = src.get();
190 if (c < 0x80) {
191 if (!dst.hasRemaining())
192 return CoderResult.OVERFLOW;
193 dst.put((byte)c);
194 mark++;
195 continue;
196 }
197 if (sgp.parse(c, src) < 0)
198 return sgp.error();
199 return sgp.unmappableResult();
200 }
201 return CoderResult.UNDERFLOW;
202 } finally {
203 src.position(mark);
204 }
205 }
206
207 protected CoderResult encodeLoop(CharBuffer src,
208 ByteBuffer dst)
209 {
210 if (src.hasArray() && dst.hasArray())
211 return encodeArrayLoop(src, dst);
212 else
213 return encodeBufferLoop(src, dst);
214 }
215
216 }
217 }